Subcutaneously implanted vascular access devices, or ports, have been used for many years to provide long term vascular access in patients that require frequent or periodic therapeutic infusions or blood draws. Currently, ports generally have a reservoir body that contains a chamber accessible by a self-sealing septum and an outlet that is connected to a catheter that is placed into the vascular system. The port is implanted into a subcutaneous pocket during a minor surgical procedure.
A disadvantage of current devices is that they generally possess a cylindrical reservoir having a circular access area to be accessed by the user. The use of a cylindrical reservoir, however, creates “corners” or angular junctions, specifically where the bottom wall of the reservoir meets the continuous side wall. The design of a cylindrical reservoir will necessarily require the side wall of the reservoir to meet the bottom wall at or about a ninety degree angle. One example of a cylindrical reservoir in an implantable infusion port is disclosed in U.S. Pat. No. 4,673,394. Although cylindrically shaped reservoirs are commonly used in such implantable devices, the angular junctions in such reservoirs may pose significant health risks to the patient over time. A major issue with implantable infusion ports is the accumulation of debris and residue over time that may eventually lead to the occlusion of the device. With current port technology, such angular junctions are present not only where the bottom wall of the reservoir meets the continuous side wall, but also where the continuous side wall meets the planar septum covering the reservoir. The use of a generally planar septum to cover the cylindrical reservoir creates an additional angular junction where the side wall of reservoir meets the planar septum. The current technology, therefore, teaches a 90 degree angled junction at both the perimeter of the bottom wall and the top edge of the side wall where the side wall meets the bottom surface of the septum thereby creating a large area in which debris and residue can accumulate and cause complications for the user. A significant drawback of the current technology is that the design of the reservoir and septum provides ample opportunity for debris and residue to accumulate which may compromise the safety of the patient over time.
What is required, therefore, is an implantable vascular access port that overcomes the drawbacks of the current technology by having a novel reservoir and septum design that attempts to eliminate angular junctions and include flow patterns within the reservoir.
In recent years, there has been a development of smaller profile ports for implantation in smaller subcutaneous spaces, such as in a patient's arm. The smaller the port; however, the smaller the septum access area must be to accomplish a small profile. A need, therefore, exists for a vascular port that provides for a smaller profile but that allows for substantial septum access area.
There has been a further development of ports having an elongated body and non-circular septum access area, such as in U.S. Pat. No. 7,850,666. While such an elongated body may provide a non-circular septum access area, it does not address the disadvantages of a cylindrically shaped reservoir since the septum is planar. The use of a planar septum and cylindrical reservoir will necessarily result in corners at the junction of the bottom and side walls of the reservoir and where the side wall meets the bottom surface of the septum. Such a design provides ample opportunity for debris and residue to accumulate over time.
Accordingly, a need exists for a vascular access port which provides a small profile for insertion through a small incision and a larger septum access area or degree of access having a novel septum and reservoir design that attempts to eliminate angular junctions and include flow patterns within the reservoir.